Re: Automake: use of modified Perl modules & GPL

[Richard Stallman]

    That I can answer: Dean Roehrich, then called Class::Template, license
    Perl 5's dual Artistic/GPL (as it was contributed directly to Perl's
    core as a standard module).  Later renamed to Class::Struct and
    modified by Jim Miner, then Damian Conway (the damian of the CC list),
    then Casey West (formerly Casey Tweten), no license changes by any of
    them.

Does "no license changes" mean that the modified version is also
released with notices saying "dual Artistic | GPL"?
In that case, the situation seems perfectly explicit and clear.